火花点火发动机顶环岸间隙处未燃碳氢生成和释放过程的数值模拟计算

NUMERICAL SIMULATION OF FORMATION AND DESORPTION OF UNBURNED HYDROCARBON IN TOP-LAND CREVICE OF SPARK IGNITION ENGINES

基于火焰传播过程建立了火花点火发动机顶环岸间隙处未燃碳氢生成和释放过程的数学模型，并利用模型进行了顶环岸间隙处未燃碳氢生成过程的数值模拟计算。计算结果表明：当汽油机燃用稀混合气、采用低压缩比、适当推迟点火提前角以及采用边缘布置火花塞等均可有效地降低顶环岸间隙内未燃碳氢的生成量，达到降低未燃碳氢排放的目的。

In this paper,based on flame propagation a mathematical model of formation and desorp-tion of unburned hydrocarbon in top-land crevice of spark ignition engines has been estab-lished.The calculation of unburned hydrocarbon formation in top-land crevice is carried outby using this model.The calculation results show that unburned hydrocarbon of top-landcrevice can be effectively reduced by means of lean mixture,low compression ratio,retardspark ignition timing and edged spark plug.